21 must-do UK triathlons: 6 Olympic-distance races

“The Slateman is a personal favourite and showcases all of Snowdonia in all its epic glory. The swim is in the clean 94-foot deep Llyn Padarn, a leg-busting bike follows around the local mountains and the run – through the comically steep Dinorwig Slate Quarries and Coed Dinorwig woodland – is like nothing I’ve experienced. All of this with a hugely supportive local population hollering from the first athlete to the last. There’s a fine post-race hog roast as well…”Matt Baird, 861st in 2014

Location: Croyde, Devon Date: JulyDistance: 1.5km | 40km | 12km “I’d say the Croyde Ocean Triathlon is the most scenic triathlon in the UK. It features a unique 1.5km ocean swim in a spectacular location with incredible views throughout. And the organisation is fantastic, too. It’s a race that you don’t want to end.” Paul Bisset, 111th in 2016

“Held since 1991 and perennially popular ever since, no other UK race oozes tri history like Windsor. How often do you get to swim in the shadow of the Queen’s gaff and bike on open roads around the Great Park? And the run is possibly the greatest 10km in UK triathlon, with that beastly Castle hill to be tackled a trio of times.” Matt Baird, 1,319th in 2011

“This popular September race attracts beginners and elites alike, with ITU pro David Bishop holding the course record. Starting on the choppy Llyn Tegid, the out-and-back bike and run routes are super fast and flat, perfect for a standard-distance PB.” Jack Sexty, 30th in 2013Race tips: Bala Standard Tri

“The Belfast Titanic Triathlon is by far the best in Northern Ireland! You’re surrounded by iconic buildings and features, with the swim in the shadow of the famous Shipyard Cranes and transition by the beautiful Customs House. The bike and run are pancake flat and there’s definitely a big chance of a PB.” Gareth Archer, 17th in 2016See also The Bristol Triathlon in June

“From the Castle Triathlon Series organisers, the Castle Howard event boasts a challenging course on quiet, relatively traffic free roads. It’s tough but very rewarding and suitable for all abilities. It also has a stunning location, exceptional organisation and a festival atmosphere offering something for everybody.” John Hardcastle, 33rd in 2016.